Paper bag



R. W. JAITE Aug. 1, 1933.

PAPER BAG 2 Sheets-Sheet 1 Filed May 29, 1931 lf l I IN VEN TOR.

ROY W- .THITE A TTORNEY.

R. w. JAITE 1,920,700

PAPER BAG.

Filed May 29, 1931 2 Sheets-Sheet 2 INVENTOR.

R0 Y W'JR/ TE M. M M

llll llll IIIIII.

RTIQL Aug. 1, 1933.

ATTORNEY.

Patented Aug. 1, 1933 l n .i

, 1,920300 PAPER, BAG

Roy WV. Iaite,

Lakewood, Ohio Application May 29,1931..' SerialNo. 541,01 7 p 1 Claim?(01. 229-62) My invention relates to paper bags, and is an improvementpertaining moreparticularly to paper bags in which the opposite 'endsare closed. such for example, as in the so-called valve t yp'e in whichthe'bo dy of the bag is' composed of a multiple or plural'humber of flattubes or tubular plies of paper, and provided with a self-closing valvein one angular corner. Such'bags are f'usually plicatedor formed withpleatedfolds at theirlongitudinal edges, and closed atboth ends, exceptfor the valve openin'gin one corner. To .close such ends the generalpractice is to s'ew.the corresponding ends'of the plies of papertogether,

- and 'also' to paste a binding striparound the end edges. Each tubularply o f'paper also possesses a pasted longitudinal overlapping seam, theends of. which are traversed by the stitches and united together andto"otheroverlapping plies in sewing operations. All the seams arelocated in the same side or in the same side Wall of the bag,

and though the seam in each successive tube is usually placed inlaterally offset relation to the seams in the other tubes it followsthat the bag is not of uniform thickness across each end where stitchedor sewed on a straight line transversely of the bag. That is, the sewedstitches which extend across the vbag ends pass through successive areasof different thickness, inasmuch as each tube in the bag is of doublethickness where seamed and only of singlethickness elsewhere, exceptingat the'valve folds. In that connection be it known that the sewingneedle passes through the thicker and thinner areas successively andpunctures the paper at close intervals, and that the tension in thethreads and on the paper may vary owing to the unequal thickness of thebag along the sewed line. y

For practical usages, paper bags of the described type are ofsubstantial size, say approximately fifteen inches wide and twenty-sixinches long in the flat. They areused extensively for transportation ofpowdered materials, for example, cement, and hold about ninety-fourpounds net. To carry that weight these bags must be made of relativelytough paper and embodya suflicient number of tubular plies to protectthe goods therein and withstand breakage andrupture, especially when thebags are being filled, and when picked up and handled. Owing to fre- 0quent breakage, and loss of contents of such bags,

' the trade at present demands that such bags shall embody at least fivetubular plies of paper of given quality and strength. However, differentpaper and a lesser number of plies of paper would sufiice'to make anacceptable bag, providing the bag would not tear or burst openespecially in the region of the seams at oppositeends :there'of. Mybjectin generaI is to provide a bag UN TE D STATE A T FF 1CIEQ made ofthe 'sameor a lesser number of plies than 7 as used and requiredheretofore,- which'jwill be stronger and more secure,xand- "overcome"the "known dangers and objections in'leakage, break- 'agefa'nd rupturein'thattypeof bag A further "object is'to prov-ideabag in which the endsare more rigidly united in sealing union without sewing -andwithoutQttaver'sing for perforating by stitching; that is, aba'giri which eachplyiresists witlf its entire cross section breakage. and rupture, all asliereinafter--morfully described and pointed out :in the appended claim.

1 Inethe accompanying drawings, Fig. 1 is aside levatiom 'and 2 an edge,view, on a reduced scale; ofapaper bag embodyingkmy invention. Figs. 3and 4 are enlarged sectional views on lines 33 and 4+4 of Fig. 1,showing the interlocking of: and sealing of the opposite walls at oneend of the bag. Fig. 5 and Fig. 6, are obverse and reverse views of thesame bag on a smaller scale,

portions of the successive tubular plies being broken away in steppedrelation to show the internal construction within the opposite sides ofthe bag. Figs. 7,8, and 9,' are diagrammatic views, corresponding tocross sectional views on lines 7-7, 8-8, and 9 9, of Figs. 4 and 5, re-

spectively; Fig. 10 is a fragmentary perspective view of a sectionalportion of the bag showing the sealing joint thereof.

Asa preliminary, it should be understood that in manufacturing multi-plybags of the kind disclosed in the drawings, a series ofv sheetsor'strips of paper are fed through a tubing machine. and creased orfolded to forma multi-ply tube A hav-" so Y ing pleats orinwardlyextending folds 2in-the longitudinal edge portions thereof. Thefsheetsare fed into the machine in superposed relation with theirparallel edgesoffset or in stepped relation so that when the sheets are jointlyfoldedto produce a. flat plicated tubular body thepar- :allel edgeportions of,each sheet will overlap and to the paper along the edge thereof so thatthe overlapping parts of the seam in each sheet are united together. Thetubular products thus embody a multiple number of seamed tubes, sleevedtogether'with the pasted seams 3 in the respecform longitudinal seams 3.Pasteis also appliecl thereof is folded inwardly to provide a valve inthe form of an-open pocket or filling opening 5', the .inturned walls ofwhich extend a given distance inwardly on lines substantially parallelwith the'transverse end edge of the sleeved tubes. While severing thetubular product in short tubes of given length, the opposite ends 6of-such tubes are simultaneously slit, preferably on converging lines'7, to form a number of tongues 8, which hesive covers each sealentirely, re-enforces same substantially and secures the tongues intheirfolded position. 7

1 As previously delineatedall the seams of the bag are located on thesame sideor in the same sidewall of the bag, so that one wallissubstantially re-enforced and thicker, even thoughthe seams are placedin laterally offset position; Any

. breakage of the'bag will therefore, of 'courseoccur in'the wall whichis not re-enforced by the overlapping layers of a seam. To avoid suchbreakageand assure equal strength of both walls of the bag one orvmore're-enforcing strips 10 of paper or other material are placedlengthwisenpon or within the plainflmseame'd ,wall r thesleve'd. tubes.The glengthot the re-enforcing strip 10;

only one of which is .used in the. three-ply bag shown in Figs. '5.through 8, corresponds to the length of the tubes so that-the oppositeends xthereof:will beconnected to and sealed with the corresponding endsof all the tubes. The width of strip 10 is more or less optional, but ispreferably chosen to correspond with the total width of all three seams.The benefits and advantages of such an arrangement are made manifest asthe body of the bag thus formed possesses the same or substantially thesame resistance to tensile strains or stresses on both sides.

In manufacturing such bagsthe strip or strips 10 may be fed togetherwith the several sheets of paper through the tubing machine, and thepaste applied and the several sheets or plies folded and .severedconcurrently with the strip or strips to provide a re-enforeed multi-plytubular body of the requisite length from which to make a bag. Thetucking of the valve and the sealing operations of the open ends of thebag may be per-- formed subsequently in another machine or in separatemachines.

What I claim, is: V i A paperbag, comprising a multiple. number ofseamed tubes, sleeved-together with their pasted seams longitudinallyarranged on the same side of the bag, a re-enforcement strip of paperex- 1 tending longitudinally upon the plain unseamed wall of the bag tothe opposite ends thereof, a

pluralityof tapered locking tongues formedby' slitting the opposite endsof said tube and said re-enforcement strip on converging lines, saidtongues being folded lalternately back'upon the opposite walls of saidbag, and abinder strip pasted to and encircling the edge of said bag andcovering said tongues, said tongues being of small width so thata'plurality ots'aid locking tongues extend over said re-enforcing stripto securely interlock said strip with the opposite ends of said bag.-

